SAN ANTONIO — What started as clash between the drivers of two cars ended with one of the cars colliding head-on with a truck, killing the car's driver and his passenger, police said Friday.

Police said the two men who died, ages 19 and 20, were in a silver Acura driving north on San Pedro around 1:15 p.m. just north of Basse Road when they got involved in an argument with another driver.

At one point, the passenger in the Acura hung out of the car's window and threw an object at the other vehicle, described by witnesses as a brown or tan sedan.

Just north of Basse Road, the driver of the Acura lost control of the car and fishtailed, causing the passenger to be thrown from the vehicle.

The driver stopped and helped the man back in the car, then took off south on San Pedro at a high speed.

The driver again lost control of the car and veered into the northbound lanes, where it collided head-on with a black pickup.

The driver and passenger were pronounced dead at the scene.

The truck driver was taken to an area hospital with a broken leg and was expected to make a full recovery.

A witness who asked not to be identified said she saw the car speeding south on San Pedro.

“I didn't see the car spin, but I saw it coming back,” she said. “He threw something at the other car, then I heard glass break. It's scary because it could have been me. I left right after it happened.”

Police are looking for the driver of the sedan, which might have some damage.